Response of Melissa officinalis Induced by Application of Pseudomonas fluorescens Isolated from Different Agro Climatic Zones of Karnataka

Abstract

Melissa officinalis is an aromatically important plant grown all over the world. It is used for different medical purposes as tonic, antispasmodic, carminative, diaphoretic, sedative-hypnotic strengthening the memory, relief of stress-induced headache and has antioxidant properties. The fluorescent Pseudomonas have emerged as the largest and potentially most promising group of the plant growth promoting rhizobacteria with their simple nutritional requirement, flexible metabolism, their short generation time and motility. Through several mechanisms, they promote plant growth and inhibit soil borne or seed borne phytopathogens. This present work is carried out in Department of Biotechnology, U.A.S., G.K.V.K., Bangalore. This study aims to isolate and identify the Psuedomonas fluorescens from rhizospheric soil from different agroclimatic zones of Karnataka. Molecular characterisation was done through the RAPD technique. The isolates found to be highly polymorphic. The RAPD bands are analysed by Statistica software. The dendrogram clearly depicted that all the isolates form two major clusters and isolates from zone 1 and zone 4 spanning the extremes. Efficient strain of Pseudomanas was screened out, which is responsible for increasing biomass of Melissa officinalis. Ten treatments of Pseudomonas fluorescens are made from ten different agro climatic zones with one control. These treatments are inoculated on 2 week-old seedlings of Melissa officinalis and allowed to grow for 60 days. Plant height, weight, chlorophyll content, total soluble sugars, and proteins are estimated at a regular interval of time. All the data are subjected to MStat C software for statistical analysis. It is observed that the Psuedomonas fluorescen isolated from zone 6 induced potentially increased growth in Melissa officinalis and is responsible for plant growth promotion.